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This paper compares the gamma‐radioactivity values determined in an intertidal ecosystem on the Atlantic island of Barra in the Western Isles of Scotland in 1989 and 1994. Distinct differences in the accumulation values in different trophic levels were detected on each occasion, but, in the intervening five years between surveys, there have also been marked reductions in the gamma counts in many different organisms of each trophic level. Gamma‐radioactivity has continued to move through the sandy soils of the machair coastal dunes system, and hence away from the rooting zone of the vegetation. The decreasing gamma‐radioactivities noted point to a shoreline ecosystem that is recovering from the input of Chernobyl fallout.

An analysis of radioactivity in organisms inhabiting the intertidal region of the Island of Skye revealed accumulation of gamma radioactivity by specific organisms, such as lichens, to be markedly enhanced as compared with other autotrophs. The movement of radioactivity through trophic levels culminating in organisms such as the predator Nucella lapillus is described. A comparison with previous work indicates a marked decrease in the gamma count in these organisms due to a variety of factors as discussed. The importance of the position of the organism on the shore during the post‐Chernobyl contaminated rainfall is reiterated.

Sediment measurement is usually accessible on a periodic or distinct basis. The measurement of sediment (suspended and bedload), especially in the field, is vital in keeping essential data of sediment transport and deposition. Various techniques for measuring sediment have been used over time each with its merits and demerits. The techniques discussed in this paper for suspended sediment include bottle, acoustic, pump, laser diffraction, nuclear and optical. Other techniques for bedload measurement are; River bedload trap (RBT), CSU/FU bedload trap, Helley–Smith, Polish Hydrological Services (PIHM) device, pit and trough, vortex tube, radioactive traces and bedload–surrogate technologies. However, the choice of technique depends on multiple factors ranging from budget constraint, availability of equipment, manpower and data requirement. The purpose of this paper is to present valuable information on selected techniques used in sediment measurement, to aid researchers/practitioners in the choice of sediment measurement technique.

This paper presents a general review of selected field techniques used in sediment measurement (suspended and bedload). Each techniques mode of operation, merits and demerits are discussed.

This paper highlights that each technique has its peculiar merits and demerits. However, two techniques are generally preferred over others; the bottle sampling and the Helley–Smith sampler for measuring suspended and bedload sediment. This is because the applicability of these techniques is quite widespread and time-tested.

This review paper provides an in-depth description and comparison of selected existing field sediment measurement techniques. The objective is to ease decision-making about the choice of technique, as well as to identify the suitability and applicability of the chosen technique.

In a previous paper (J. Doc. 20 (4) 1964, 212–35) a series of tests on the coverage, overlap, and indexing of abstracts journals were described. Briefly, these were carried out by selecting recent, comprehensive bibliographies on specific subjects, searching the appropriate abstracts journals via the author indexes to determine the number of references given in the bibliography that were abstracted, then consulting the subject indexes to try to locate those references which are known to have been abstracted. A further eight bibliographies have been studied, and the results are reported here.

Radon is responsible for approximately 50 per cent of public exposure to environmental radiation. The purpose of this paper is to quantitatively assess indoor radon levels in Cyprus.

In total, 500 passive radon detectors were used to estimate radon levels in the areas of Nicosia (capital), Paphos, Nisou and Famagusta. A total of 240 different public and private buildings were randomly selected in the above districts and two passive radon detectors were placed inside each building. The detectors were collected on average, three months following placement.

The average radon level from all passive detectors was 53.7 and 49.2 Bq/m3 after excluding the seven highest values. The two highest measurements were observed in Paphos, Tsada-Kili elementary school (429 Bq/m3) and Emba, Paphos district (410 Bq/m3), respectively. Differences were also seen in public buildings compared to private buildings (p=0.058). In addition, rural buildings had higher radon levels compared to urban buildings (p=0.001). Predictive multilevel regression models for logarithmic radon levels were employed and differences were seen on point estimates regarding building- and district-level radon measurements. Most of the random variability observed was due to building-level variation.

Residents from different geographic areas in Cyprus are reassured about the safety of indoor radon levels in public and private buildings.

The estimation of indoor radon levels was done by the optical microscopy technique using a specific mathematical formula. Observed radon levels do not raise concern regarding residents’ radon exposure in Cyprus. Paphos district and Nisou area may require further investigation.